Views: 28 Author: Site Editor Publish Time: 2026-06-09 Origin: Site
API Grade (Diesel) | Closest ACEA Equivalent | Main Regions Using Each Standard |
|---|---|---|
API CF / CF‑4 | ACEA E2 / E3 (obsolete) | North America (API primary); South America (API + local registration); Middle East (both API & ACEA accepted) |
API CI‑4 / CI‑4 PLUS | ACEA E7 (for EGR engines) | Europe (ACEA mandatory for modern trucks); Japan (JASO preferred, API accepted for older imports) |
API CJ‑4 / CK‑4 | ACEA E9 (low‑SAPS, for DPF/SCR) | Europe (Euro V/VI require ACEA E9 or API CK‑4); Global – best for new engines with after‑treatment |
Simple rule:
Europe → use ACEA (E7 or E9)
USA / Canada / Middle East / South America → API (CI‑4 or higher) is fine
Japan → JASO (DH‑2) or API CI‑4
Property | Old (CD / CF) | Modern (CI‑4 / CK‑4) | Customer Benefit |
|---|---|---|---|
Soot handling | Low – oil thickens quickly | High dispersancy (CI‑4+) | Longer drain interval, less sludge |
Heat resistance | Poor – oxidises fast | Strong antioxidants | Oil lasts longer in hot engines |
Wear protection | Basic ZDDP | Advanced anti‑wear package | Less cam & ring wear, especially with EGR |
TBN (acid fighting) | TBN 5–8, depletes fast | TBN ≥10–12, better retention | Neutralises acidic fuel, prevents corrosion |
Shear stability | Viscosity drops under load | Shear‑stable polymers | Maintains oil pressure under heavy work |
After‑treatment safety | High ash, phosphorus, sulphur | Low‑SAPS options (CJ‑4/CK‑4) | Protects DPF & SCR (Euro IV+) |
Real‑world difference: Upgrading from CF to CI‑4 roughly doubles oil life and significantly reduces engine deposits.
Engine type: Small generator, water pump, or agricultural engine – no turbo, no EGR, no DPF – runs hot (air‑cooled).
Standard | Minimum Grade | Why? |
|---|---|---|
API | CF (or better: CF‑4 / CI‑4) | CF is the lowest that withstands air‑cooled heat. CD or lower will cause ring sticking and oil thickening. CF‑4/CI‑4 give better oxidation control. |
ACEA | E7 (or A3/B4) | ACEA E2/E3 are obsolete. E7 is safe and backward‑compatible. A3/B4 (light‑duty high‑performance) also works well. |
Do NOT use:
API CD or lower (outdated, unreliable)
Low‑SAPS oils like ACEA C3 or API CK‑4 unless the engine has a DPF (it doesn’t) – they may have lower TBN and can wear out faster with high‑sulphur fuel.
“For your small air‑cooled diesel engine, use API CF as the absolute minimum. For better protection and longer oil life, choose API CI‑4 or ACEA E7. Avoid old grades like CD, and avoid modern low‑SAPS oils unless your engine has exhaust after‑treatment.”
